Nitrites Detection with Sensors Processed via Matrix-Assisted Pulsed Laser Evaporation

Abstract

This work is focused on the application of a laser-based technique, i.e., matrix-assisted pulsed laser evaporation (MAPLE) for the development of electrochemical sensors aimed at the detection of nitrites in water. Commercial carbon-based screen-printed electrodes were modified by MAPLE via the application of a newly developed composite coating with different concentrations of carbon nanotubes (CNTs), chitosan, and iron (II) phthalocyanine (C32H16FeN8). The performance of the newly fabricated composite coatings was evaluated both by investigating the morphology and surface chemistry of the coating, and by determining the electro-catalytic oxidation properties of nitrite with bare and modified commercial carbon-based screen-printed electrode. It was found that the combined effect of CNTs with chitosan and C32H16FeN8 significantly improves the electrochemical response towards the oxidation of nitrite. In addition, the MAPLE modified screen-printed electrodes have a limit of detection of 0.12 µM, which make them extremely useful for the detection of nitrite traces.

Polypyrrole–Tungsten Oxide Nanocomposite Fabrication through Laser-Based Techniques for an Ammonia Sensor: Achieving Room Temperature Operation

“…PLD is used for obtaining mesoporous WO 3 layers onto which a thin layer of PPy is applied via MAPLE. Additional details about the setups and the method can be found in [ 8 , 27 ]. Briefly, the PLD experimental setup consists of a YAG:Nd pulsed laser (Quantel, France) (266 nm wavelength, repetition rate of 10 Hz, 7 ns pulse duration) and an in-house designed reactive chamber connected to vacuum pumps.…”

Highly Sensitive Graphene-Based Electrochemical Sensor for Nitrite Assay in Waters

“…Among these, due to its rapidity, sensibility and low costs, the electrochemical aproach has become one of the most popular and extensively used analytical tools [26]. To create electrochemical sensors with increased sensitivity and accuracy for nitrite detection, different nanomaterials have been embedded on electrode surfaces: nickel/PDDA/reduced graphene oxide [27], Ag-Fe 3 O 4 -graphene oxide magnetic nanocomposites [28], Fe 3 O 4 -reduced graphene oxide composite [29], metalorganic framework derived rod-like Co@carbon [30], La-based perovskite-type lanthanum aluminate nanorod-incorporated graphene oxide nanosheets [31], cobalt oxide decorated reduced graphene oxide and carbon nanotubes [32], gold-copper nanochain network [33], carbon nanotube (CNTs), chitosan and iron (II) phtalocyanine (C 32 H 16 FeN 8 ) composite [34]; gold nanoparticles/chitosan/MXenes nanocomposite [35], worm-like gold nanowires and assembled carbon nanofibers-CVD graphene hybrid [36]; photochemically-made gold nanoparticles [37], or graphene nanoparticles [38]. Among these, the special properties of graphene are unequivocal and long-time recognized [39], justifying their extensive applicability and usage in sensors technology [40,41].…”